New Zealanders Lieutenant Andrew Dougall Blair and Sub-Lieutenant W.E Sanders VC., DSO were early Q-Ship operators during the First World War. Since 1914 ﻿Germany had been using submarines to attack both Naval ships and commerical vessels. Even when armed, commercial vessels had little chance of a good defence. Rear Admiral Gordon Campbell, VC., DSO described in his book My Mystery Ships the response to this menace.

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The idea was therefore conceived of fitting merchant ships as men-of-war, with a specially trained crew aboard and a concealed armament strong enough to destroy a submarine if encountered. To all intents and purposes they would look like ordinary innocent merchant ships, and would therefore entice the submarine to them.

This class of ship went under various titles. Their real function was decoying, and the proper title would, therefore, appear to be " decoy ships," but it was not secret enough. The Admiralty in the early days referred to them as "special service vessels," and the ships themselves were known in the dockyards and so on as S.S.-- The fact that a number of people in and about the dock-yards and naval ports knew that the Master of S.S. -- was a naval officer, that special guns and gadgets were being fitted, and that no one except on duty was allowed on board, naturally gave ground for them being referred to as "Mystery Ships," and I don't think for quite a long while that many people knew what duty these vessels were really employed on, although of course some must have suspected. Towards the latter part of 1916 the Admiralty gave them all "Q" numbers, and they became Q-ships.